Releaseable joint for joining two construction elements and transportable construction comprising same

ABSTRACT

A releasable joint for joining two construction elements of a transportable construction. Also a construction element adapted for use in making the releasable joint, and a construction, such as a portable building or stage assembly, comprising a plurality of construction elements joined by the releasable joint.

The present invention relates to a releasable joint for joining twoconstruction elements of a transportable construction. The inventionalso includes a construction element which is adapted for use in makinga releasable joint in accordance with the invention, and a constructionsuch, for example, as a portable building or stage assembly comprising aplurality of the construction elements which are joined releasably oneto another by a releasable joint in accordance with the presentinvention.

Transportable stage assemblies are used in the entertainments industryfor providing stages at venues which do not include permanent stages insitu. For example, in the music industry, transportable stage assembliesare commonly used for staging concerts in large capacity venues such,for example, as multi-purpose "exhibition" halls, sports stadia andoutdoor locations in fields or on pasture land. A typical transportablestage assembly comprises an elevated stage area constituted by aplurality of floor panels supported by scaffolding, and a roofconstruction disposed above the stage area for carrying a weatherproofcanopy for shielding performers and equipment on the stage area from theweather, stage lighting and other equipment for use during the concert.At the time of writing, such a roof construction is typically supportedby scaffolding disposed in juxtaposition with the side margins of thestage area.

It will be understood by a person skilled in the art that it isdesirable for a transportable stage assembly to be capable of assemblyand disassembly in as short a time as possible. The cost of hiring avenue can be very expensive, and it is desirable therefore to reduce asfar as possible the time required for setting up and dismantling thestage assembly.

Furthermore, in the case of transportable stage assemblies used by theentertainments industry for tours comprising performances at a pluralityof successive venues typically one shortly after another, there is ageneral requirement to reduce the time taken to set up and dismantle thestage assembly to reduce the possibility of mistakes in assembly anddisassembly of the stage which is typically carried out by local workforces at each venue, and to minimise the volume occupied by the stageassembly when packed in order to reduce the cost of transporting thestage assembly from one venue to the next. To this latter end, inparticular, there is a general requirement to make each component of atransportable construction and the connections between such componentsas strong as possible so as to reduce the overall volume of componentsneeded to make a construction of a given specification. Clearly thefewer components that are needed, the less the transport capacity thatwill have to be provided.

In order to meet some or all of the above mentioned requirements theinventors have developed the present invention which, in one aspect,provides a releasable joint for joining two construction elements of atransportable construction such, for example, as a stage assembly orbuilding, said releasable joint comprising:

one end of one construction element;

a spigot member, one end of which spigot member is carried by the oneend of the one construction element and another end of which spigotmember has a first aperture formed therein;

another end of another construction element which defines a recessadapted to receive the other end of the spigot member and has a secondaperture formed therein which can be aligned with the first aperturewhen the other end of the spigot member is received in the recess;

a non-threaded spigot securing member which can be entered into thefirst and second aligned apertures; and

a releasable securing means for securing releasably the spigot securingmember in the first and second aligned apertures;

the arrangement being such that, in service, the other end of the spigotmember can be entered into the recess such that the first and secondapertures are aligned one with the other, whereafter the non-threadedspigot securing member can be entered into the first and second alignedrecesses thereby to secure the other end of the spigot member in therecess, thereby to join releasably the one end of the one constructionelement to the other end of the other construction element, and thespigot securing member can itself be secured in place by the releasablesecuring means.

The present invention therefore provides a means for joining theconstruction elements of a transportable stage assembly one to anotherwhich facilitates rapid assembly and disassembly of the stage assembly.In particular, the use of a non-threaded spigot securing member forsecuring the other end of the spigot member in the recess of the otherend of the other construction element eliminates the need to use nutsand bolts for securing the construction elements together which, it willbe understood, is significantly more time consuming than the use of thenon-threaded spigot securing member of the present invention,particularly when the threads of such nuts and bolts become damagedthrough repeated use.

In another aspect of the present invention there is provided aconstruction element for use in making a releasable joint in accordancewith the present invention, said construction element comprising firstand second ends, wherein one of said first and second ends carries oneend of a spigot member, another end of which spigot member has a firstaperture formed therein, and the other end of the construction elementdefines a recess which is adapted to receive the other end of anotherspigot member of another similar construction element, and has a secondaperture formed therein which can be aligned with the first aperture ofthe other spigot member when the other end of the other spigot member isreceived in the recess of the one construction element.

The present invention also comprehends, in yet another aspect, atransportable construction comprising a plurality of constructionelements in accordance with the other aspect of the present invention,wherein said construction elements are joined releasably one to anotherby a releasable joint in accordance with the one aspect of the presentinvention. Said construction, in some embodiments may be a transportablestage assembly or a portable building, marquee or the like.

Said construction may comprise a roof. In a particular aspect of theinvention, the construction may comprise a tower for supporting a roof.

Typically, the construction will comprise a roof and a plurality oftowers for supporting the roof. Where the construction is a stageassembly, an elevated stage will additionally be provided.

In some embodiments the construction elements for use in the roof may beinterchangeable with the construction elements for use in a tower,thereby reducing the total number of different parts which need to beused as compared with prior art transportable stage assemblies, and thussimplifying the assembly/disassembly of the construction.

Said non-threaded spigot securing member may comprise a non-threaded pinhaving a head portion and a stem portion which can be entered into thesaid first and second aligned apertures. Typically, the releasablesecuring means may comprise a releasable clip which can be inserted intoan open bore formed through the stem portion remote from the headportion; said releasable clip may be a split pin or an R-clip.

In some embodiments of the invention, the spigot member maybe formedintegrally with the one end of the one construction element.Alternatively, the one end of the spigot member maybe fixedly secured ina recess formed in the one end of the one construction element. The oneend of the spigot member may be secured in the recess e.g.semi-permanently by means of one or more bolts entered into alignedapertures formed in the one end of the one construction element and theone end of the spigot member and fixedly secured in place bycorresponding nuts. In another embodiment of the invention, the one endof the spigot member may be welded in the recess.

Typically, the construction element in accordance with the invention maycomprise a truss comprising a plurality, typically two spaced,substantially parallel, elongate chord portions which are braced bybracing means. Typically, each chord portion maybe constituted by ahollow tube. Said tube may be rectilinear or circular in cross section,typically square or rectangular.

The recess formed in the one end of the construction element and theother, first-mentioned recess formed in the other end may each beconstituted by the bore of one of the chord portions in juxtapositionrespectively with the one and other ends of the construction element.

In some embodiments, the recesses formed in the one and other ends maybe substantially identical one to the other. Typically, each of thechord portions may define a first recess at the first end of theconstruction element and a second recess at the second end such that theone construction element can be joined releasably to the other, similarconstruction element by means of a plurality of releasable joints inaccordance with the present invention.

Said bracing means may comprise a plurality of brace portions which aredisposed generally transversely of the elongate chord portions. Thus, incertain embodiments of the invention, the truss may be generallyrectangular, having two long sides defined by parallel, elongate thechord portions. The brace portions may include two end braces disposedone at or towards each of the longitudinal first and second ends of thetruss and extending substantially transversely therebetween to form theshort sides of the rectangle. In addition the brace portions willtypically comprise at least one diagonal brace portion which extendsbetween the two chord portions in direction having components in thelongitudinal and transverse directions.

The construction elements forming the construction in accordance withthe invention may be arranged in two or more spaced, substantiallyparallel rows (in the case of a roof) or columns (in the case of atower). Each row may comprise a plurality of construction elements, eachjoined one to another by at least one releasable joint in accordancewith the one aspect of the invention.

Each row or column may be releasably secured to a neighbouring row orcolumn by a releasable bracing means. Typically, said releasable bracingmeans may comprise a plurality of spaced releasable brace means. Thereleasable bracing means will usually be employed to brace one truss ofone row or column with a corresponding truss in a neighbouring row orcolumn as the case may be. Thus, where rectangular trusses of the kinddescribed above are employed, the construction will, in each row orcolumn, comprise a series of box-like structures formed of twocooperating trusses and associated bracing means which the Applicantshave found to posses great load-bearing strength.

In some embodiments, each releasable brace means may comprise a bracemember having first and second ends, wherein each of said first andsecond ends is releasably secured to a respective construction elementincluded in a respective one of the neighbouring rows or columns by areleasable brace securing means.

Said releasable brace securing means may comprise a bracket member whichis carried on the end of the brace member, and bracket securing meansfor securing the bracket member releasably to the respectiveconstruction element. Typically, said bracket member may have anaperture formed therein which can be aligned with a correspondingaperture formed in the respective construction element; a non-threadedbracket securing member can be entered through the aligned apertures andretained in position by a releasable securing means, such or example asa split-pin or an R-clip.

In accordance with a further aspect of the present invention, at leastone brace member may be secured, at one end, to a respectiveconstruction member in juxtaposition with said other end of therespective construction element, and the aperture formed in the bracketmember may be aligned with the said second aperture formed in the otherend of the respective construction element and the first aperture formedin the other end of the spigot member, and may be secured releasably tothe respective construction element by the non-threaded spigot securingmember which is entered through the aligned apertures formed in thebracket member, the other end of the construction element and the spigotmember. The bracket member itself may be fixedly secured to the end ofthe brace member as for example by welding.

Thus, at least one of the spigot securing members included in theconstruction, in addition to securing releasably the spigot member inthe recess formed in the other end of the other construction element mayalso be used to secure releasably the one end of the brace member to theother end of the other construction element. Such an arrangement has theadvantage of reducing the total number of parts required for assemblingthe structure in accordance with the present invention and for reducingthe number of operations, and thus the time, required for such assembly.

As mentioned above, the Applicants have found that the use of trussesdescribed herein to form towers for supporting a roof has the advantagethat such towers are significantly stronger than the scaffolding used inthe prior art for this purpose. For a roof having a payload of the orderof say forty tons, only six towers in accordance with the presentinvention may be required (only four towers may be needed where apayload of less than forty tons is required). It will be understood by aperson skilled in the art therefore that for a construction of a givenspecification, the present invention will require fewer components andthus occupy less space when disassembled and packed, for example ontolorries, as compared with the prior art stage assemblies which employscaffolding for supporting the stage roof. The use of towers inaccordance with the invention may therefore significantly reduce thecost of transporting a construction such as a stage assembly from onevenue to another on a tour.

The present invention is not restricted to transportable stageassemblies, but can be used to form portable buildings to providetemporary venues of up to potentially very large capacities, by buildinga roof to cover the desired area, and providing the number of towersrequired to support the roof at the desired height. The roof and towerscan, if desired, be covered by a weather-proof canopy to protect theenclosed space.

In a particular aspect of the present invention, a tower constructionmay be provided with a pivot means between two neighbouring trussestowards the lower end of the erect tower, such that the upper portion ofthe tower above the pivot means can be assembled horizontally on theground from its constituent construction elements and then raised intoits erect position by pivoting it by the pivot means.

A hydraulic ram may be used to apply the turning moment necessary aboutthe pivot means for lifting the upper part of the tower to its erectposition. Where a plurality of towers are to be erected, the ram can bemoved about the site from one tower to another on a movable "dolly". Areleasable coupling means may be provided for coupling releasably thepiston(s) of the ram to the tower for lifting. The ram can then bedecoupled and moved to the next tower.

Typically, the pivot means may be incorporated in a pivotableconstruction element which is adapted for forming releasable joints withthe upper and lower parts of the tower in the manner herein described,and includes releasable coupling means for coupling to the hydraulicram.

Following is a description by way of example only with reference to theaccompanying drawings of methods of carrying the present invention intoeffect:

In the drawings:

FIG. 1 is a schematic front elevation of a simplified stage assemblyaccording to the present invention.

FIG. 2 is a schematic plan view of the simplified stage assembly of FIG.1.

FIG. 3 is a side elevation of a construction member according to thepresent invention.

FIG. 4 is a side elevation of a releasable joint in accordance with thepresent invention.

FIG. 5 is an isometric view of a part of the joint of FIG. 4.

FIG. 6 is an enlarged plan view showing a detail of the simplified stageassembly of FIGS. 1 and 2.

FIG. 7 is a side view of another releasable joint for a tower accordingto the invention.

FIG. 8 is a side elevation of a tower bracket member.

FIG. 9 is a plan view of a tower base member in accordance with thepresent invention.

FIG. 10 is a side elevation of the tower base member of FIG. 8.

FIG. 11 is an isometric view of an actual stage assembly in accordancewith the invention.

FIG. 12 is an isometric view of a part of the actual stage assembly ofFIG. 11, showing a part of a roof and three towers.

FIG. 13 is a plan view of another actual stage assembly in accordancewith the present invention.

FIG. 14 is an isometric view of a part of the other stage assembly ofFIG. 13.

FIG. 15 is a side elevation of a truss in accordance with the invention.

FIG. 16 is a plan view of a brace member.

FIG. 17 is a side view of the brace member of FIG. 16.

FIG. 18 is a side view of a pick-up truss in accordance with theinvention.

FIG. 19 is a plan view of a roof-lower landing frame.

FIG. 20 is a side elevation of the roof lower landing frame of FIG. 19.

FIG. 21 is a plan view of a roof upper landing frame.

FIG. 22 is a side view of the roof upper landing frame of FIG. 21.

FIG. 23 is a side view of a tower landing base.

FIG. 24 is a side view of the tower landing base of FIG. 23, partly incross-section on the line A--A.

FIG. 25 is a side view of an extension truss for the tower landing baseof FIGS. 23 and 24.

FIG. 26 is an isometric view of part of a tower including a pivot unitin accordance with the present invention.

FIG. 27 is an isometric view of a part of the tower of FIG. 26 showingdetail of the pivot unit.

FIG. 28 is an isometric view of a transportable building in accordancewith the present invention.

A simplified stage assembly which is shown in FIGS. 1 and 2 is describedfirst to illustrate the principal features of the present invention. Thesimplified assembly includes a roof (20) supported by a plurality ofupstanding towers (30). Each tower (30) is supported on the ground by atower base (40). The stage assembly also includes an elevated stage (50)(see FIG. 1) comprising a plurality of rectangular floor panels disposedone contiguous another so as to form a continuous floor surface; thefloor panels are supported by a scaffolding (not shown).

In the simplified embodiment shown in the drawings, the roof (20) issupported by four towers (30); each tower (30) is joined juxtaposed itsupper extremity (32) to the roof (20) for supporting the latter. It willbe appreciated that in practice different numbers of towers (30) can beused in accordance with the present invention depending on the requiredpayload of the roof (20). The Applicants have found for a stage assemblyof the kind typically required by the entertainments industry forconcert tours, that six such towers (30) are suitable for supporting aroof (20) having a payload up to about forty tons; fewer towers than sixcan be used for payloads less than forty tons.

The roof (20) is generally rectangular in plan view (see FIG. 2) and hasan up-stage end (22), a down-stage end (23) and first and second sides(24,25) respectively which extend between the up- and down-stage ends(22,23) substantially orthogonally to the cross-stage direction.

The roof (20) is formed in the main from a plurality of trusses (100)(see FIG. 3) which are joined releasably one to another to form aplurality of rows (26) as shown in FIG. 2, which rows are spaced onefrom another in the up/down-stage direction. The simplified example ofthe invention illustrated in FIGS. 1 and 2 has four rows (26); each row(26) is formed of nine trusses (100). It will be appreciated howeverthat in practice different numbers of rows and trusses (100) can be usedin accordance with the present invention to provide a roof of sufficientdimensions to cover the desired stage area, and to carry all theequipment and lighting required for use during a concert.

With reference to FIG. 3, each truss (100) comprises first and secondspaced, substantially parallel, elongate chord portions (102,104) which,in the assembled roof (20) are spaced vertically one from the other.Each of said first and second chord portions (102,104) extends between afirst end (106) and a second end (107) of the truss (100) and isconstituted by a length of steel tube of substantially rectangular orsquare cross-section.

Said first and second chord portions (102,104) are interconnected by afirst transverse brace portion (108) which extends between the firstends (106) of the first and second chord portions (102,104); a secondtransverse brace portion (110) which extends between the second ends(107) of the first and second chord portions (102,104), and a diagonalbrace portion (112) which extends between the first end of the firstchord portion (102) and the second end of the second chord portion(104). Each of the first and second transverse brace portions and saiddiagonal brace portion (112) is constituted by a length of steel tube ofsubstantially rectangular or square cross-section.

The first chord portion (102) is drilled juxtaposed its first end (106)to provide a first hole (114) (indicated by the chain dotted line inFIG. 3) which extends substantially vertically through the upper andlower walls of the first chord portion (102). Said hole (114) isoverlaid on the exterior surface of each of said upper and lower wallsby a cheek plate (116) which is welded to said exterior surface and isdrilled to provide a hole in alignment with the hole (114) through thefirst chord portion (102). The purpose of the cheek plates (116) is toreinforce the chord portion (102) in the area of said first hole (114).

The first chord portion (102) is provided with a second hole (118) injuxtaposition with the second end (107) of the first chord portion(102), which second hole (118) is reinforced by cheek plates (116) inthe same way as said first hole (114).

The second chord portion (104) is also provided with first and secondholes (120,122) in the same way as the first chord portion (102) as showin FIG. 3.

Each truss (100) is releasably joined to its neighbouring truss(es)(100) within its row (26) by a releasable joint as shown in FIG. 4. Thismethod of joining two construction members (100) is common to thesimplified example shown in FIGS. 1 and 2 and to more sophisticatedconstructions which will be used in practice as hereinafter described.

Said releasable joint comprises a first spigot member (130) and a secondspigot member (132). Each of said first and second spigot members(130,132) is constituted by a length of steel tube of generallyrectangular or square cross-section and has a first end (134) and asecond end (136). Each of said first and second spigot members (130,132)is dimensioned to form a close fit, within a reasonable manufacturingtolerance, in the bore defined by one of said first and second hollowchord portions (102,104), and is drilled in juxtaposition with saidfirst end (134) to provide a hole (140) which extends substantiallyvertically through the upper and lower walls of the spigot member(130,132) and in juxtaposition with said second end (136) to provide asecond similar hole (142). Each spigot member including a male end thatenters an open end of a next section.

As shown in FIGS. 4 and 5, the second end (136) of the first spigotmember (130) is entered into the bore (138) defined by the first end(106) of the first chord portion (102) of one of the trusses to bereleasably secured (100a). The second hole (142) formed in said firstspigot member (130) is aligned with the first hole (114) formed in thefirst chord portion (102), and a bolt (144) is entered through thealigned holes (114,142) and is secured in place by means of acorresponding nut (146).

Similarly, the first end (134) of the second spigot member (132) isentered into the bore (138) defined by the second end (107) of thesecond chord portion (104) of the other truss to be joined (100b) and issecured therein by means of a nut and bolt (144,146) as described above.

The second and first ends (136,134) of the first and second spigotmembers (130,132) respectively can be left in their corresponding bores(138) permanently.

In order to secure releasably the two trusses (100a,100b) one to theother, the first and second ends (106,107) of the trusses (100a,100b)are brought into juxtaposition one with the other; the first end (134)of the first spigot member (130) is entered into the bore (138) definedby the second end (107) of the first chord portion (102) of the othertruss (100b). Simultaneously, the second end (136) of the second spigotmember (132) is entered into the bore (138) defined by first end of thesecond chord portion (104) of the one truss (100a). The first hole (140)formed in the first end (134) of the first spigot member (130) isbrought into alignment with the second hole (118) formed in the secondend (107) of the first chord portion (102); and the second hole (142)formed in the second end (136) of the second spigot member (132) isbrought into aligned with the first hole (120) formed in the first end(106) of the second chord portion (104) of the one truss (100a).

In each case, a non-threaded pin (150) is then entered through thealigned apertures (118,140;120,142). Said pin (150) comprises a headportion (152) which abuts on the exterior surface of the correspondingcheek plate (116) and a non-threaded stem portion (154) which extendsthrough the aligned holes (118,140;120,142). Said stem portion (154) isdrilled to provide a bore (156) therethrough remote from said headportion (152). In the fitted position, said bore (156) is disposedoutside the corresponding chord portion (102;104) and cheek plate (116);a releasable R-clip (158) is entered through the bore (156) to securereleasably the non-threaded pin (150) in the aligned holes(118,140;120,142).

In this way, each truss (100) is joined to its neighbouring truss(es)(100) at two spaced locations. The use of the non-threaded pins (150)and releasable retaining R-clips (158) facilitates rapid assembly anddisassembly of the trusses one from another, and thus of the entireconstruction (20).

Each truss (100) is also secured releasably to a corresponding truss(100') in its neighbouring row(s) (26) by a plurality of braces (200);in the embodiments of the invention illustrated in FIGS. 2 and 6, eachtruss (100) is releasably secured to the corresponding truss (100') inthe neighbouring row (26) by two such braces (200). A first brace (202)extends between the second end (107) of the first chord portion (102) ofone truss (100) and the second end (107') of the first chord portion(102') of the corresponding truss (100') of the neighbouring row (26); asecond brace (204) extends between the first end (106) of the secondchord portion (104) of the one truss and the first end (106') of thesecond chord portion (104') of the corresponding truss (100'). Forconvenience, FIG. 6 shows the first brace (202) which extends betweenone truss (100) and the corresponding truss (100') in the neighbouringrow, and the second brace (204) which extends between the next adjacentpair of corresponding trusses (100,100').

Each of said first and second braces (202,204) which extends between therow (26) juxtaposed the up-stage end (22) of the roof construction(20)--designated as row (26a) in FIGS. 2 and 6--and the neighbouring row(26) on the down-stage side--designated as row (26b)--comprises anintermediate tube portion (206) having an up-stage end (208) and adown-stage end (210); said intermediate tube portion (206) isconstituted by a length of steel tube of generally square or rectangularcross-section.

The up-stage end (208) carries a pair of spaced upper and lower plates(210,212) on its upper and lower surfaces respectively. Each of saidplates (210, 212) is welded on the up-stage end (20B) and extends awayfrom said up-stage end (208) in the up-stage direction, as shown in FIG.6, by distance about equal to the width of the corresponding chordportion (102;104) in the up-stage-down-stage direction transverse thefirst and second ends (106,107) of the truss (100). Said upper and lowerplates (210, 212) define a recess therebetween in juxtaposition withsaid up-stage end (208), which recess accommodates the corresponding end(106;107) of the corresponding chord portion (102;104) of the truss(100) of the up-stage row (26a).

Each of said upper and lower plates (210,212) has a hole formed therein(214) which is aligned with the aligned holes (118,140;120,142) in thecorresponding end of the corresponding chord portion and thecorresponding end of the corresponding spigot member (130;132). The pin(150) extends through the holes (214) formed in the upper and lowerplates (210,212), thereby to secure releasably the up-stage end (208) ofthe brace (202;204) to the corresponding truss in the up-stage row(26a).

The down-stage second end (210) of each of said first and second braces(202,204) also carries a pair of spaced upper and lower plates(218,220). The upper and lower plates (218,220) on the down-stage end(210) of the brace (202;204) differ from the plates (210,212) on theup-stage end (208) in that the plates (218,220) on the down-stage end(210) extend away from the intermediate tube portion (206) in thedown-stage direction by distance approximately twice the transversewidth of the corresponding chord portion (102';104'); each of said upperand lower plates (218,220) on the down-stage end (210) has two holesformed therein, an up-stage hole (222) and a down-stage hole (224).

The upper and lower plates (218,220) on the down-stage end (210) of thebrace (202;204) define a recess therebetween which accommodates thecorresponding end (106';107') of the corresponding chord portion(102';104') of the truss (100') of the neighbouring row (26b). Theup-stage holes (222) are aligned with the aligned holes(118',140';120',142') in the corresponding end of the correspondingchord portion (102';104') and the corresponding end of the correspondingspigot member (130';132); the non-threaded pin (150') is entered throughthe up-stage holes (222) to secure releasably the down-stage end (210)of the brace (202;204) to the corresponding truss of the neighbouringrow (26b).

Thus each truss (100) in each row is releasably secured to acorresponding truss (100') in a neighbouring row to form a box-likestructure. The Applicants have found that a construction such as theroof (20) herein described formed in this way from such trusses (100,100') by releasable joints has a good weight/performance ratio, and can,for a given packed volume of components, be assembled to form aconstruction having a higher load-bearing capacity as compared withprior art constructions having the same packed volume.

Each truss (100) of the row (26) forming the down-stage end (23) of theroof construction (20)--designated as row (26d) in FIG. 2--is joined toits neighbouring row in the up-stage direction--designated row (26c)--bymeans of braces (200) in the same way as between rows (26a) and (26b).

Neighbouring rows (26b) and (26c) are secured releasably one to theother by a plurality of braces (300) which are not illustrated indetail. Each of the braces (300) is constituted simply by a length ofsteel tube of generally square or rectangular section having an up-stageend and a down-stage end, each of which up-stage and down-stage ends hasa hole drilled therethrough which extends substantially verticallythrough the upper and lower walls of the tube. The up-stage end of eachbrace (300) is accommodated in the recess defined by the upper and lowerplates (218,220) on the down-stage end (210) of a corresponding one ofthe braces (200) which extend between the rows (26a) and (26b) such thatthe holes drilled in the up-stage end of the brace (300) are alignedwith the holes (224) formed in said upper and lower plates (218,220) ofthe corresponding brace (200); a non-threaded pin of the kindhereinbefore described is entered through the aligned holes to securereleasably the up-stage end of the brace (300) between the upper andlower plates (218,220) of the corresponding brace (200). The down-stageend of the brace (300) is secured releasably in similar fashion betweenthe upper and lower plates (218,220) of a corresponding one of thebraces (200) which extend between the rows (26d) and (26c).

Each tower (30) comprises two spaced, upright columns (34). As shown inFIGS. 1 and 2 each column is constituted by two trusses (100) securedreleasably one to another by means of releasable joints as hereinbeforedescribed. It will be understood however that more than two columns canbe employed if desired. Of course, each tower truss (100) is orientedsuch that the first and second chord portions (102,104) are disposedsubstantially vertically. Each tower may be assembled for use in areclined position on the ground and then erected to the position shownin FIG. 1 by lifting the upper extremity of the tower to rotate thetower through 90°. Alternatively, the tower may include a pivot means ashereinafter described.

Each of the upright columns (34) is secured releasably to the othercolumn by a plurality of braces (400) as shown in FIGS. 2 and 7. In theexample shown in FIG. 7, the ends of three braces (400)--one horizontalbrace (400') and two--diagonal braces (400")--are releasably secured injuxtaposition with two neighbouring trusses (100a,100b) in one of thecolumns (34); the other ends (not shown) of the three braces (400) aresecured releasably to a corresponding pair of neighbouring trusses(100') in the other column (34').

The ends of the braces (400) are secured releasably to the neighbouringtrusses (100) by means of a tower bracket member (410) as shown in FIGS.7 and 8. Said tower bracket member (410) comprises three substantiallyvertically disposed plates (412,414,416) which are secured fixedly toone another to form a structure which is H-shaped in cross-section; thetower bracket (410) further includes a horizontally disposed plate (418)which is welded to each of the vertically disposed plates (412,414,416)to provided an internal abutment and two vertically spaced upper andlower recesses (420,422) respectively in juxtaposition with one surface(424) of the middle plate (414) of the H-shape. The bracket member (410)defines a vertically disposed channel (426) in juxtaposition with theother surface (428) of the middle plate (414). One of the outer plates(412) of the H-shape is cut out as shown in FIG. 7 in juxtaposition withthe vertically disposed channel (426) in order to accommodate thejuxtaposed first and second transverse brace portions (108,110)respectively of the neighbouring trusses (100a,100b) of the one column(34). Both outer plates (412,416) are drilled as shown in FIG. 7 toprovide first and second holes (430,432) aligned respectively with thenon-threaded pin (150) which extends through the corresponding end ofthe corresponding chord portion (102;104) of one of the neighbouringtrusses (100b) and the bolt (144) which extends through thecorresponding end of the corresponding chord portion (102;104) of theother neighbouring truss (100a). The non-threaded pin (150) and bolt(144) pass through the respective holes (430,432) to secure the bracketmember releasably to the one truss (100b) and semi-permanently to theother truss (100a), with the said other surface (428) of the middleplate (414) disposed contiguous the juxtaposed surfaces of the chordportions (102,102;104,104;) of the neighbouring trusses (100a,100b).

The outer plates (412,416) are also drilled as shown in FIGS. 7 and 8 toprovide vertically spaced holes (434,436,438) aligned with correspondingholes formed in the ends of the three braces (400) for releasablysecuring the ends of the braces (400) in the upper and lower recesses(420,422) as shown in FIG. 7, by means of non-threaded pins (not shown)of the type hereinbefore described.

Each tower base (40) comprises a central landing base (500) as shown inFIGS. 9 and 10 which comprises two vertically spaced upper and lowerframes (502,504). Each of said upper and lower frames (502,504) isconstituted principally by four lengths of steel tube of square orrectangular cross-section which are secured fixedly one to one anotherin a substantially square configuration as shown in FIG. 9. Each of theupper and lower frames (502,504) is reinforced by a diagonal brace (508)(see FIG. 9) which is welded to and extends between diametricallyopposed corners of the square frame (502;504).

The upper and lower frames (502,504) are interconnected at their cornersby four substantially vertically disposed braces (510) and by eightdiagonal braces (512).

At each corner, the upper frame (502) carries two substantiallyhorizontally disposed, mutually orthogonal "starter spigots" (514) andone substantially vertically disposed "starter spigot" (516).

Each of the columns (34) of a corresponding tower (30) is releasablysecured at its lower extremity (33) to the landing base (500) by meansof a respective pair of the vertically disposed starter spigots (516)which are drilled to provide holes which can be aligned with the holesformed in the mating ends of the chord portions (102,104) of thecorresponding column (34), in order to allow the column (34) to besecured releasably to the landing base (500) by means of non-threadedpins (not shown) as hereinbefore described.

The horizontally disposed starter spigots (514) are also drilled asshown in FIGS. 9 and 10 for connection to outwardly extending trusses(100) as shown in FIG. 1 to provide a generally eruciform base ofsufficiently large area for supporting the tower (30). Each of theoutwardly extending trusses (100) is secured releasably to the landingbase (500) by a releasable joint in the manner described above.

If further ballast is required in the tower bases (40), water bags ortanks can be attached to the tower bases and filled with water in situto provide an additional stabilizing mass at the bases of the towers(30).

Having described a simplified embodiment of a construction in accordancewith the present invention, FIGS. 11 and 12 show, as another example, anactual stage assembly in this case comprises a roof (20) which issupported by four upstanding towers (30). It will be seen that theprinciple of construction of the roof (20) and towers (30) is the sameas for the simplified embodiment hereinbefore described; the roof (20)and towers (30) are constructed in the main from a plurality of trusses(100) which are secured releasably one to another by means of areleasable joint as herein described.

The embodiment illustrated in FIGS. 11 and 12 additionally comprises two"outrigger" assemblies (600) juxtaposed the side margins (24,25) of theroof (20). Each out rigger assembly (600) includes a beam (610) which iscarried by one of the towers (30) supporting the roof (20) and anadditional tower (30) spaced from the one tower in the cross-stagedirection. The additional tower (30) is of substantially the sameconstruction as each of the towers (30) supporting the roof (20); thebeam (610) is also made up from trusses (100) in the same way as theroof (20) which are joined one to another end-to-end and in rows whichare interconnected by braces as described above. The beams (610) can beused for supporting additional equipment for use during e.g. a concert.

It will also be noted that the towers (30) on either side (24,25) of theroof (20) are interconnected by a plurality of stays (612) forreinforcement. Conveniently, the ends of the stays (612) can each beconnected to a juxtaposed releasable joint between two trusses (100) bymeans of the non-threaded pin (150) forming part of the joint.

FIG. 13 shows a six tower construction in which the roof (30) includesadditional diagonal brace members (614) between neighbouring rows (26)of trusses (100) around the periphery of the roof (20). For thispurpose, the braces (200) extending between neighbouring rows (26) injuxtaposition with the roof periphery as described above are modified toinclude additional bracket portions for mounting the diagonal bracemembers (614). An example of a modified brace (200) for use in securingthe juxtaposed ends of two diagonal brace members (614) at points suchfor example as that illustrated at (616) in FIG. 13 is illustrated inFIGS. 16 and 17. The modified brace (200) includes an intermediatetubular member (206) and upper and lower plates (210,212,218,220) on theup-stage and down-stage ends (208,210) of the brace (200) in the sameway as the unmodified braces (200) shown in FIG. 6. Additionally howeverthe up-stage end (208) of the brace (200) carries upper and lowerlaterally extending plates (618,620) which define two recesses (622) onein juxtaposition with each cross-stage side of the brace (200). Thelaterally extending plates (618,620) are drilled to provide holes (624)in the same way as the upper and lower plates (210,212,218,220) on theup-stage and down-stage ends (208,210) of the brace (200), and each ofthe recesses (622) accommodates an end of one of the diagonal bracemembers (614) which is drilled in alignment with the holes (624) and issecured releasably in the recess (622) by means of a non-threaded pin(150) of the kind described above.

The other diagonal brace members (614) around the periphery of the roof(20) are also secured releasably to juxtaposed brace members (200) whichare modified in an analagus manner to the modified brace member of FIGS.16 and 17. For instance, laterally extending plates (618,620) will onlybe required to one cross stage side of a brace member (200) as forexample at the point indicated at (624) in FIG. 13.

The construction of the rooves (20) of the stage assemblies shown inFIGS. 11 and 12 and FIG. 13 is shown in more detail in FIG. 14. The roof(20) is formed from a plurality of trusses (100) of the kind shown inFIG. 15 comprising first and second chord portions (102,104), first andsecond transverse end brace portions (108,110), cheek plates (116) andholes (114,118,120,192) in the same way as the truss (100) shown in FIG.3. As compared with truss (100) of FIG. 3, however the truss (100) ofFIG. 15 constitutes a "double" truss in that it comprises anintermediate transverse brace portion (626) and two diagonal braceportions (112) as shown in FIG. 15. The first and second transverse endbrace portions (108,110) are also provided each with two verticallyspaced holes (628) and associated cheek plates (630), such that inaddition to the releasable "pin and spigot" joint as hereinbeforedescribed, each truss (100) can be secured releasably to itsneighbouring truss(es) by means of non-threaded pins (150) insertedthrough the holes (628) in the juxtaposed ends (106,107) of theneighbouring trusses.

With reference to FIG. 14, the sides (24,25) of the roof (20) are formedeach by a plurality of pick-up trusses (640) of the kind illustrated inFIG. 18. The design of each pick-up truss (640) is substantially thesame as the "double" truss of FIG. 15, and each pick-up truss (640) isjoined releasably to a neighbouring pick-up truss(es) (640) by means ofa releasable joint of the kind described herein, save in that thenon-threaded pins (150) pass through the walls of the upper and lowerchord portions (102,104) and through the inter-connecting spigots (130)in the cross-stage direction between the two sides (24,25) of the roof(20), rather than vertically as shown in FIGS. 4 and 5. Furthermore,each of the upper and lower chord portions (102,104) is provided withthree spaced catch members (624) which are formed by shaped metal plateswelded onto the upper and lower chord portions (102,104) as shown inFIG. 18. The spacing between the catch members (642) in theupstage-down-stage direction is the same as the inter-row spacing of theroof (20), and each catch member (642) receives the end of a spigot(130) projecting from the end-most truss (100) of a respective row (26).The end of the spigot (130) is secured releasably between the plates ofthe catch member (642) by means of a non-threaded pin of the kinddescribed above which passes through holes drilled through the catchmember (642) and the end of the spigot (130).

The roof (20) is connected to each of the towers (30) in the embodimentsshown in FIGS. 11 and 12 and FIG. 13 by means of a roof lower landingframe (650) as shown FIG. 19 and 20 and a roof upper landing frame (652)as illustrated in FIGS. 21 and 22. The roof lower landing frame (650) isformed from four main tubular elements (4,5,6) formed into a square asshown in FIG. 19. At each corner of the square, the lower landing frame(650) is provided with up-standing and depending starter spigots (658)to mate with neighbouring trusses (100) disposed above and below thelower landing frame (650) by means of releasable joints as hereindescribed. The square is reinforced by means of a diagonal brace (660).Two of the tubular elements (656) forming opposite sides of the squarewhich extend in the up-stage-down-stage direction extend beyond thesquare to form projecting arms (662). Each of the arms (662) carries acatch member (642) formed from shaped metal plate welded onto the arms(662) of the kind included in the pick-up trusses (640) described above.The projecting arms (662) are reinforced by bracing limbs (664) as shownin FIG. 19.

The roof lower landing frame (650) is carried by cured on two trusses(100) and carries two further trusses (100) above the roof lower landingframe (650). These latter trusses (100) carry the roof upper landingframe (652) thereon. The roof upper land frame (652) as illustrated inFIGS. 21 and 22 is constructed similarly to the roof lower landing frame(650) and is secured releasably to the trusses (100) below it bydepending starter spigot (658). The projecting arms (662) of the roofupper landing frame (652) include side mounted catch members (642)however, while in the roof lower landing frame (650) the catch members(642) are mounted on upper surfaces of the projecting arms (662). Ineach case the catch members (642) on the projecting arms (662)juxtaposed the sides (24,25) of the roof (20) receive the ends of thespigots (130) projecting from the end most trusses (100) at theextremities of the rows (26). The ends of the projecting spigots aresecured in the catch members (642) by means of non-threaded pins (150)to form releasable joints of the kind described above. The load of theroof (20) is therefore carried on the projecting arms (662) of the rooflower landing frame, and the coupling between the roof upper landingframe (652) and the upper chord portions (102) of the end most trussesof the rows (26) form a cantilever with the connection between the chordportions (104) and the lower landing frame (650).

From FIGS. 11 and 13, it will be seen that the upper and lower landingframes (650,652) of the towers which do not carry an out river assembly(600) include only two projecting arms (662) in juxtaposition with thesides (24,25) of the roof (20). The upper and lower landing frames(650,652) of FIGS. 19 to 22 are suitable for use for towers (30) whichcarry an out rigour assembly (600) such, for example, as that shown inFIG. 14. The catch members (642) on the projecting arms (662) remotefrom the sides (24,25) of the roof (20) of the upper and lower landingframe (650,652) can be used to form a cantilever coupling withprojecting spigot members (130) projecting from the extremities of thetrusses (100) constituting the beam (610) of the out rigour (600).

As described above with reference to FIGS. 9 and 10, each of the towers(30) of the simplified stage assembly is supported on tower landing base(500). In the examples illustrated in FIGS. 11 and 12 and FIG. 13 a moresophisticated tower landing base (700) is employed as shown in FIGS.(23,24,25,26). With reference first to FIGS. 23 and 26, each towerlanding base (700) includes two-spaced parallel tower base trusses(710), each of which includes two-spaced upstanding starter spigots(516) for mating with the lower trusses (100) of the tower (30). The twotower base trusses (710) are oriented in use in the cross-stagedirection as shown in FIG. 26 and, in juxtaposition with each starterspigot (516), each of the tower base trusses (710) is provided with twoshort projecting truss portions (712) which extend in theup-stage-down-stage direction. In the assemble position, one of eachpair of short projecting truss portions (712) associated with a givenstarter spigot (516) is directed towards a respective short projectivetruss portion (712) on the other tower base truss (710). These aresecured together through a short truss (100) in the up-stage-down-stagedirection using releasable joints of the invention. The remaining oneprojecting truss portions (712) of each pair projects outwardly of thetower landing base and can be connected to an extension truss (714) asshown in FIG. 25 as required. With reference to FIG. 26, juxtaposedextension trusses (714) can be coupled together at spaced locationsusing short trusses (100).

As described above, the tower landing base (700) carries two columns(34) of trusses (100), the two columns being secured releasably one theother by braces (400).

In the embodiments shown in FIGS. 26 and 27 of the drawings,intermediately second and third trusses (100) counting up from the towerlanding base (700) goes interposed a pivot unit (750). Said pivot unit(750) comprises a upper and lower landing portions (752,754) which aresecured fixedly one to the other through a pivot (756), the axis ofwhich extends horizontally along one side of the pivot unit (750). Eachof the upper and lower landing portions (752,754) is provided withstarter spigots (not shown) for connecting to the trusses (100) disposedabove and below the pivot unit (750). The pivot unit (750) furthercomprises locking means (not shown) for locking the pivot unit in aclosed position as shown in Figures (26,27). The upper landing portionof the pivot unit (750) includes two spaced couplings (758) for couplingthe upper landing portion (752) to two spaced pistons (not shown) eachdriven by a hydraulic ram.

The lower part of the tower (30) will be constructed manually in situ toa height which is convenient and safe for a work force working on ornear the ground. The pivot unit (750) will then be mounted on the lowerpart of the tower in an open position. The upper part of the tower abovethe pivot unit will then be built in a reclined position connected tothe upper landing portion (752) of the pivot unit (750). The hydraulicrams can then be connected to the couplings (758) and operated to liftthe upper part of the tower (30) to the erected position.

Conveniently, the hydraulic rams can be provided on a transportabledolly having carriage means adapted for translation movement over theground, such that the hydraulic ram can be moved from one tower toanother for erecting each tower in turn.

As mentioned above, in addition to stage assemblies of the kindhereinbefore described, the construction of the present invention may bea transportable building such for example, as that illustrated in FIG.28. The building of FIG. 28 comprises 16 towers (30) and a roof (20) ofthe kind hereinbefore described carried by three pairs of towers (30) atone end of the building. The remaining five pairs of towers are joinedto the roof and to each other by means of single or double rows oftrusses (100) connected one to another by releasable joints inaccordance with the invention to form a skeleton for carrying a canopy(780). It will be appreciated that more or fewer towers (30) can be useddepending on the capacity required of the building, and a greater orlesser surface area of roof (20) can be employed depending on therequirements and pay laid of the building.

The constructions hereinbefore described are assembled principally froma plurality of trusses (100) which can be releasably secured one toanother by means of releasable joints in accordance with the invention.The stage construction is therefore susceptible of rapid assembly anddisassembly and offers a significant advantage where the time availablefor assembling and disassembling such a construction is limited orexpensive. The construction can be a building or a stage assembly, andthe number and size of the components can be adjusted to provide aconstruction of a desired specification. In particular the Applicantshave found the use of trusses as hereinbefore described formed intospaced rows or columns provides a constructions of great strength whichoccupies less packed volume when disassembled as compared with prior artscaffolding constructions of similar specifications.

In particularly convenient aspect of the invention, the Applicants havefound that the use of a pivotable tower as described herein obviate theneed for cranes to erect the towers, and this is particularlyadvantageous as it permits the erection of a construction in accordancewith the invention in locations to which a crane cannot yet access.

We claim:
 1. A releasable joint for a transportable construction, saidreleasable joint comprising:first and second construction elements, eachconstruction element comprising first and second spaced, substantiallyparallel, elongate chord portions, each chord portion having first andsecond ends and defining a recess in at least one of said ends, andbracing components for bracing said first and second chord portions;first and second spigot members, each spigot member having first andsecond ends, one end of one of the spigot members being fixedly securedto one end of one of the chord portions of one of the constructionelements, and the other end is accommodated within a recess in one endof one of the chord portions of the other construction element, and oneend of the other spigot member being fixedly secured to one end of theother chord portion of one of said construction elements, and the otherend of the other spigot member being received in a recess in the one endof the other chord member of the other construction element, the otherend of each of said spigot members having a first aperture formedtherethrough that can be aligned with a respective second apertureformed through the one end of the respective chord portion when theother end of the spigot member is received in the respective recess;first and second non-threaded spigot securing members, each spigotsecuring member is entered into a respective pair of said aligned firstand second apertures for retaining the other end of each spigot memberin the respective recess; and first and second releasable securingcomponents, each securing component releasably securing a respective oneof the spigot securing members in the respective pair of aligned firstand second apertures.
 2. A releasable joint as in claim 1, wherein eachend of each chord portion defines a recess, and the one end of eachspigot member is fixedly secured in the recess formed in the one end ofthe respective chord portion.
 3. A releasable joint as in claim 1wherein each non-threaded spigot securing member comprises a nonthreadedpin having a head portion and a stem portion, which stem portion can beentered in the respective pair of first and second aligned apertures. 4.A releasable joint as in claim 3 wherein each releasable securingcomponent comprises a releasable clip, particularly a split pin or anR-clip, which releasable clip can be inserted into an open bore formedthrough the stem portion of the respective spigot securing member remotefrom the head portion.
 5. A releasable joint as in claim 1, wherein eachof said chord portions and spigot members is of rectangular or squarecross-section.
 6. A transportable construction comprising a plurality ofconstruction elements that are joined releasably one to another byreleasable joints in accordance with claim
 1. 7. A transportableconstruction as in claim 6 which comprises a roof.
 8. A transportableconstruction as in claim 6 which comprises a tower for supporting aroof.
 9. A transportable construction as in claim 6 comprising a roofand at least one tower wherein the construction elements for use in theroof are interchangeable with the construction elements for use in thetower.
 10. A transportable construction as in claim 6 wherein theconstruction elements forming the construction are arranged in two ormore spaced, substantially parallel rows or columns, each row or columnbeing secured releasably to a neighboring row or column by a releasablebracing.
 11. A transportable construction as in claim 10 wherein thereleasable bracing comprises a plurality of spaced, releasable braces,each releasable brace bracing a respective construction element in onerow or column with a corresponding construction element in a neighboringrow or column.
 12. A transportable construction as in claim 11, whereineach releasable brace comprises a brace member having first and secondends, and first and second releasable brace securing components forreleasably securing each of said first and second ends respectively to arespective construction element included in a respective one of theneighboring rows or columns, which releasable brace securing componentcomprises a bracket member, components for securing the bracket memberto the brace member, and bracket securing components for releasablysecuring the bracket member to the respective construction element. 13.A transportable construction as in claim 12, wherein said bracket memberhas an aperture formed therethrough, sold aperture being aligned with acorresponding aperture formed in the respective construction element;and said bracket securing component comprises a non-threaded bracketsecuring member which is entered through the aligned apertures andretained in position by a releasable securing component.
 14. Atransportable construction as in claim 13, wherein at least one bracemember is secured, at least at one of said first and second ends, to therespective construction member in juxtaposition with the one end of therespective construction element, the aperture formed in the bracketmember being aligned with the said first and second aligned apertures,and said bracket member being secured releasably to the respectiveconstruction element by the said non-threaded spigot securing memberthat is entered through the aperture formed in the bracket member andsaid first and second aligned aperture formed respectively in the oneend of the construction element and in the other end of the respectivespigot member.
 15. A transportable construction as in claim 6, furthercomprising a tower, wherein said tower is provided with a pivot betweentwo neighboring construction elements such that an upper portion of thetower above the pivot can be assembled horizontally on the ground fromits, constituent construction elements and then raised into its erectposition by pivoting it about said pivot.
 16. A transportableconstruction as in claim 6, wherein a plurality of said constructionelements each consist essentially of two spaced, parallel, elongatechord portions, and bracing components for bracing said chord portions.